Russia says that its diplomats in Washington formally reached out to US officials and have briefed them on an impending plan by al-Qaeda insurgents in Idlib to stage a false flag chemical attack in order to provoke a Western military strike on Damascus.

This week Moscow has claimed to be in possession of firm intelligence that it says shows armed groups in Idlib are transporting chemicals to area sites, in preparation for the coming major Syrian Army and Russian offensive on the contested province in northwest Syria.

Anatoly Antonov, the Russian ambassador in Washington, confirmed to the media on Wednesday that he had met with the US special representative to Syria, James Jeffrey, and David M. Satterfield, acting assistant secretary of state for near eastern affairs.